Two-cycle internal-combustion engine



Feb. 19, 1952 DE LAAGE 2,586,621

TWO-CYCLE INTERNAL-COMBUSTION ENGINE i l. l\ I? Z l Filed Feb. 27, 1948 INVENTOR ALBIN o: LA-AGE gim /01; 'f 44 ATTORN E Patented Feb. 19, 1952 TWO-CYCLE INTERNAL-TCGMBUSTIQN ENGINE Albin dc Laage, Paris, France Application :February 27, I948, .Serial;N0. :1"1,'572 .InF-rance May'20, 19.46

Section '1,-Public Law 690, August 8,1946 Patent expires May 20, 1966 3 Claims.

'.'Ihiswinvention'rlates to a two-cycle internal H combustion engine. The essential characteristic of this engine resides in the fact that the com- ;pressionchamber is formed by amovable sleeve which is disposed between the cylinder and the piston (in the .manner of a four-cycle engine without valves). 'The movable sleeve is closed at its lower end and cooperates with the lower surface of the piston to cause pre-compression of the-feed air and to actat the same time as a distributor for thecompression chamber and the correspondin explosion chamber. Another fea- .ture of the invention which results from the closing of the lower end of the-sleeve is that one .or more of the connecting :rods operate on the piston head from a-lateral position.

In the schematic drawings annexed and which are given as examples only:

Figures '1, 2 and 3 illustrate "the constituent parts of this engine in three different positions during the two movements occurring in the cycle;

Figure 4 is a sectional view of the engine taken at right angles to that shown in Figures 1, 2 and 3.

The two-cycle engine, which is the object of this invention, has in the usual manner an exhaust opening I and, at approximately the same height, an opposed inlet opening 2 which is connected through a lateral tube 3' with an opening 4 with the compressor. The openin and closing of these openings 2 and 4 are controlled by the relative positions of the piston 6 with respect to the corresponding cylinder 5.

In accordance with the invention, the compression chamber is formed by a movable sleeve 1 which is disposed between the bore of the engine cylinder and its piston 6. This sleeve 1 is closed at its lower end by the bottom or closure 8 and it thus forms, in combination with the lower surface of the piston 6, a compression pump. The sleeve 7 is also provided in its walls with a number of openings 9, III, II and I2 corresponding to the openings l, 2, 3 and 4 in the cylinder 5; these openings will provide, during the rectilinear movement of the sleeve 1 in opposite directions, a distributing system for the explosion chamber and the compression chamber. The sleeve 1 is controlled or driven by a connecting rod l3 which is connected to a handle 14 of the crank shaft l5.

Since the sleeve 1 is closed at its lower end, the piston axle 6 can no longer be driven by a connecting rod extending into the interior of the piston. The piston axle l6 therefore extends at one or both of its ends so as to pass through registering slots formed in the walls of the cylin- .2 der 5 and in the sleeve 1. "Ihe-end-or ends :0! the piston axle receive the end or ends of-"corresponding laterally disposed connecting rods 15 which drive one ortwo crank handles L1, :as the case maybe, on "the crank shaft. 'The prank handles which respectively operate the piston head 6 and the sleeve '1 are locked to the shaitt approximately apart. The .crank handles are also of unequal length, because thelength of travel of the piston '6 and sleeve l .should be 'difierent. v

The phases of theopera'tion of'this enginenre the following, by reference to the "figurespf the schematic drawing attached:

Figure lshows the beginning of the expansion phase, after explosion, the piston having started on its downward travel; the corresponding-crank handle i'i having passed its high dead point. The crank handle -I'4-which is moving the 'sleeve -l downwardly is approaching its low dead point. All of the openings in the sleeve 1 are covered and the relative movement of the piston, being more rapid than the bottom '8 of the compression cylinder during this phase, results in the compression of gases that may be contained in the compression cylinder. In practical application, the piston will have two acting surfaces, so that it will have a fiat face on the compressor side as well as on the expansion or drivin side.

As soon as the crank handle it of the compressor has passed its lower dead point (the drive ing crank handle i1 continuing its downward travel), the compression increases, because the piston and the bottom 8 of the compression cylinder approach each other until the opening ID of the sleeve 1 unmasks the inlet opening 3 for fresh gas.

Figure 2 shows the end of the expansion phase and the beginning'of the exhaust phase. The opening 9 in sleeve I unmasks the exhaust opening l for the burnt gases, then after this the two openings 2 and 4 oi the tube 3' connecting the compressor chamber with the explosion chamber but the piston has not yet attained its low dead point so that the opening 2 of tube 3' is still closed by the latter. The opening 2 is unmasked by the movement of the piston 6 for the admission of the gas mixture to the explosion chamber, then the sleeve 1, having restarted its upward movement, will close the exhaust opening I to thus avoid the loss of a certain amount 01' fresh gas by seepage.

Figure 3 shows the start of the following stage. The piston 6 starts to rise again while the sleeve 1 ends its upward travel. The space between the piston 6 and the bottom 8 of the sleeve 1 will increase while the following happens: The sleeve I unmasks the inlet opening 3 while closing the lower opening 4 of the communicating tube 3'. The exhaust opening I of the explosion chamber is screened by the sleeve '1, and the piston 6 in rising will close the upper opening 2 of the tube 3'. The compressor will suck in a, volume of fresh gas which it will then push into the explosion chamber as a result of or during the following cycle.

One may note that as a result of the opposite movements of the piston head 6 and the sleeve 1, it is possible to have, for the compressor, a

cylindrical volume that is larger than the cylindrical volume of the explosion cylinder which assures a complete replenishment. As can be noted from the drawing, the connecting rod I3 is eccentrically connected to the movable sleeve in a manner to lengthen the fresh gas intake period and to shorten the compressor-discharge period,

.-comprising a cylinder, a piston, a movable sleeve between the piston and the cylinder, openings in said cylinder for the intake and exhaust and to receive a passage connecting the upper and lower portions of the cylinder, openings in said sleeve arranged to expose the proper cylinder opening in the desired sequence in accordance with the movement of the piston and sleeve, and an engine shaft, the improvement which comprises a closure-entirely sealing the lower end of said movable sleeve, a driving connection extending from said closure to the engine shaft for imparting up and down movement to said sleeve, vertical registering slots in the concentric walls of the cylinder and sleeve, a rod connected to the piston and passing through said registering slots, and a driving connection located outside of said cylinder and extending from the protruding portion of said rod to the engine shaft.

2. The improvement in two-cycle combustion engines as claimed in claim 1, in which a plurality of vertical registering slots, rods and outside driving connections are provided.

3. The improvement in two-cycle combustion engines as claimed in claim 1, in which the driving connection for the sleeve closure is connected eccentrically thereto so as to prolong the time of the sleeves downward movement and diminish the time of the sleeves upward movement.

' ALBIN DE LAAGE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 893,480 Goodrich July 14, 1908 928,405 Simon July 20, 1909 1,127,265 Longard Feb. 2, 1915 1,386,572 Jeantet Aug. 2, 1921 1,413,974 De Cosmo Apr. 25, 1922 1,415,096 Kallwitz 1 May 9, 1922 1,533,727 De Cosmo Apr. 14, 1925 FOREIGN PATENTS Number Country Date 239,520 Great Britain June 10, 1926 

